Re: [css3-break] Transforms, Positioning, and Pagination

Hi fantasai,

I have some questions about this new text in the fragmentation spec.

On Dec 1, 2012, at 12:37 AM, fantasai <fantasai.lists@inkedblade.net> wrote:

> I had an action item to draft text for the resolutions from TPAC here:
>   http://www.w3.org/mid/50A33BC0.9050903@inkedblade.net
> 
> Here's the proposed text, with annotations:
> 
>   | Fragmentation interacts with layout, and thus occurs <em>before</em>
>   | relative positioning [[!CSS21]], transforms [[!CSS3-TRANSFORMS]],
>   | and any other graphical effects.
> 
> [This takes care of the resolution on relpos and transforms.]
> 
>   | However, the separation and transfer of page boxes SHOULD occur last;
>   | thus a transformed fragment that spans pages SHOULD
>   | be sliced at the page breaks and print in its entirety
>   | rather than being clipped by its originating page.

1. This second part refers strictly to pagination, not other fragmentation specifications such as multi-column or regions, right?

> 
> [This is new; I suspect it's necessary to print many pages without dataloss.
> I am unsure whether anybody implements it, however.]
> 
>   | Absolute positioning affects layout and thus interacts with
>   | fragmentation. Both the coordinate system and absolutely-
>   | positioned boxes belonging to a containing block fragment
>   | across pages in the same fragmentation flow as the containing
>   | block.

2. Small nit: If this is to be applied general across the fragmentation specs, I think using words like "pages" should be avoided.

> 
> [This handles the clarifications to how abspos interacts with fragmentation.]
> 
>   | UAs are not required to correctly position that span a
>   | fragmentation break and whose before edge position depends on
>   | where the box's content fragments.
>   | UAs with memory constraints that prevent them from manipulating
>   | an entire document in memory are not required to correctly
>   | position absolutely-positioned elements that end up on a
>   | previously-rendered page.
> 
> [The first one is hard. The second one is not needed for browsers,
> but was a concern for e.g. printer implementations.]
> 
> Comments welcome.
> 
> ~fantasai
> 

3. Do we have a text that covers what should happen with the CSS transforms coordinate systems when dealing with fragmentation? Maybe it would be worth mentioning each fragment gets its own coordinate system (so rotating a box with two fragments around its centre would rotate each fragment around its own centre).

Thanks,
Andrei.

Received on Thursday, 10 January 2013 15:28:02 UTC